Display apparatus and control method thereof

ABSTRACT

A display apparatus is provided. The display apparatus includes: a communication interface including a circuit; a display panel configured to be selectively driven at any one of a plurality of frame rates; and a processor configured to: identify an input frame rate of a video, based on the video being received through the communication interface, adjust a setting value of the display panel so that the display panel operates at a frame rate among the plurality of frame rates that corresponds to the input frame rate, and control the display panel to output the received video, by driving the display panel at the frame rate corresponding to the input frame rate.

CROSS-REFERENCE TO RELATED APPLICATION(S)

This application is a continuation of U.S. application Ser. No.17/081,665, filed Oct. 27, 2020 (allowed), which is based on and claimspriority under 35 U.S.C. § 119 to Korean Patent Application No.10-2020-0036146, filed on Mar. 25, 2020, in the Korean IntellectualProperty Office, and claims the benefit of U.S. Provisional ApplicationNo. 62/934,731, filed on Nov. 13, 2019, in the U.S. Patent and TrademarkOffice, the disclosures of which are incorporated by reference herein intheir entireties.

BACKGROUND 1. Field

The disclosure relates to a display apparatus and a control methodthereof, and more particularly, to a display apparatus for changing aframe rate, and a control method thereof.

2. Description of Related Art

Recently, with the development of a technology for a display apparatus,a display apparatus having a high scan rate has been developed toimprove video quality.

However, when a frame rate (or a scan rate) of a panel provided in thedisplay apparatus is different from a frame rate of a video, a delaytime may occur, and, thus, a problem may occur that a video that isoriginally intended to have an improved quality is lagged or is notseamless when the video is provided to a user.

For example, in the related art, when the frame rate of the video is lowand the frame rate of the panel is relatively high, there is a problemthat an input lag of about 8.3 ms is generated until the video is outputafter calculation for a frame configuring the video is performed.

SUMMARY

Provided are a display apparatus that changes a frame rate of a displaypanel and outputs a video, and a control method thereof.

According to embodiments, the display panel may be driven at theplurality of frame rates without changing a panel structure of thedisplay apparatus.

According to embodiments, by allowing the frame rate of the video andthe frame rate of the display panel to coincide, it is possible tominimize occurrence of an input lag and provide a video that is notlagged and is seamless to a user.

According to embodiments, it is possible to control whether or not tochange the frame rate of the display panel according to a controlcommand and control whether to output a video as it is or add aninterpolation frame to the video and then output the video.

Additional aspects will be set forth in part in the description whichfollows and, in part, will be apparent from the description, or may belearned by practice of the presented embodiments of the disclosure.

In accordance with an aspect of the disclosure, a display apparatusincludes: a communication interface including a circuit; a display panelconfigured to be selectively driven at any one of a plurality of framerates; and a processor configured to: identify an input frame rate of avideo, based on the video being received through the communicationinterface, adjust a setting value of the display panel so that thedisplay panel operates at a frame rate among the plurality of framerates that corresponds to the input frame rate, and control the displaypanel to output the received video, by driving the display panel at theframe rate corresponding to the input frame rate.

The processor is further configured to adjust at least one of a dynamiccapacitance compensation (DCC) value for compensating for a responsespeed of the display panel, a liquid crystal charging timing of thedisplay panel, or a luminance of the display panel, that are included inthe setting value, based on the input frame rate.

The plurality of frame rates include a first frame rate and a secondframe rate having a frequency higher than a frequency of the first framerate, and the DCC value and the liquid crystal charging timing that areincluded in a setting value corresponding to the first frame rate aregreater than the DCC value and the liquid crystal charging timing thatare included in a setting value corresponding to the second frame rate.

The plurality of frame rates include a first frame rate and a secondframe rate having a frequency higher than a frequency of the first framerate, and the processor is further configured to: identify the inputframe rate as corresponding to the second frame rate, increase the DCCvalue and the liquid crystal charging timing based on a setting valuecorresponding to the first frame rate, based on the frame rate of thedisplay panel being changed from the second frame rate to the firstframe rate, and adjust the luminance of the display panel so that agamma value of the display panel is maintained equal to a referencegamma value.

The processor is further configured to: change a frame rate of thedisplay panel based on a user command for changing the frame rate of thedisplay panel, and drive the display panel, based on the user command.

The processor is further configured to: control the display panel todisplay a user interface (UI) for changing the frame rate of the displaypanel, and adjust the setting value of the display panel so that thedisplay panel operates at a frame rate corresponding to the user commandinput through the UI.

The processor is further configured to identify the input frame rate ofthe received video based on metadata of the received video.

The processor is further configured to: analyze the received video toobtain video processing delay information related to processing of thereceived video, and identify the input frame rate of the received videobased on the video processing delay information.

The video processing delay information is determined based on at leastone of type information of the received video, user interaction relatedinformation, or object information in the received video.

In accordance with an aspect of the disclosure, a control method of adisplay apparatus including a display panel configured to be selectivelydriven at any one of a plurality of frame rates includes: identifying aninput frame rate of a video, based on the video being received;adjusting a setting value of the display panel so that the display paneloperates at a frame rate among the plurality of frame rates thatcorresponds to the input frame rate; and controlling the display panelto output the received video, by driving the display panel at the framerate corresponding to the input frame rate.

The adjusting the setting value includes adjusting at least one of adynamic capacitance compensation (DCC) value for compensating for aresponse speed of the display panel, a liquid crystal charging timing ofthe display panel, or a luminance of the display panel, that areincluded in the setting value, based on the input frame rate.

The plurality of frame rates include a first frame rate and a secondframe rate having a frequency higher than a frequency of the first framerate, and the DCC value and the liquid crystal charging timing that areincluded in a setting value corresponding to the first frame rate aregreater than the DCC value and the liquid crystal charging timing thatare included in a setting value corresponding to the second frame rate.

The plurality of frame rates include a first frame rate and a secondframe rate having a frequency higher than a frequency of the first framerate, the identifying the input frame rate includes identifying theinput frame rate as corresponding to the second frame rate, and theadjusting the setting value includes: increasing the DCC value and theliquid crystal charging timing based on a setting value corresponding tothe first frame rate, based on the frame rate of the display panel beingchanged from the second frame rate to the first frame rate; andadjusting the luminance of the display panel so that a gamma value ofthe display panel is maintained to be equal to a reference gamma value.

The adjusting the setting value includes changing a frame rate of thedisplay panel based on receiving a user command for changing the framerate of the display panel.

The control method may further include displaying a user interface (UI)for changing the frame rate of the display panel, wherein the adjustingthe setting value includes adjusting the setting value of the displaypanel so that the display panel operates at a frame rate correspondingto the user command input through the UI.

The identifying the input frame rate of the video includes identifyingthe input frame rate of the received video based on metadata of thereceived video.

The control method may further include analyzing the received video toobtain video processing delay information related to processing of thereceived video, wherein the identifying the input frame rate of thevideo includes identifying the input frame rate of the received videobased on the video processing delay information.

The video processing delay information is determined based on at leastone of type information of the received video, user interaction relatedinformation, or object information in the received video.

In accordance with an aspect of the disclosure, there is provided anon-transitory computer-readable medium storing at least one instructionthat, based on being executed by a processor of a display apparatus,causes the display apparatus to perform a method of: identifying aninput frame rate of a video, based on the video being received;adjusting a setting value of a display panel so that the display panel,which is capable of being selectively driven at any one of a pluralityof frame rates, operates at a frame rate among the plurality of framerates that corresponds to the input frame rate; and controlling thedisplay panel to output the received video by driving the display panelat the frame rate corresponding to the input frame rate.

In accordance with an aspect of the disclosure, a display apparatusincludes: a panel driver; a display panel which is drivable by the paneldriver at a plurality of frame rates and is configured to displaycontent at any one of the plurality of frame rates; and a processorconfigured to: identify an input frame rate of a video being received bythe display apparatus based on a parameter included in the video, theinput frame rate being different from a second frame rate of the displaypanel at which content has been previously displayed, among theplurality of frame rates, based on the input frame rate being different,adjust a response speed setting value of the display panel so that thedisplay panel starts operating at a first frame rate among the pluralityof frame rates that corresponds to the input frame rate, and control thedisplay panel to output the received video, by controlling the paneldriver to drive the display panel at the first frame rate correspondingto the input frame rate.

The second frame rate has a frequency higher than a frequency of thefirst frame rate, the response speed setting value is set differentlyfor the first frame rate and the second frame rate, and the processor isfurther configured to: based on the second frame rate being changed tothe first frame rate, increase the response speed setting value incorrespondence to the first frame rate, and adjust a luminance of thedisplay panel so that a gamma value of the display panel remains at aconstant level.

The processor is further configured to: based on the first frame ratebeing changed to the second frame rate, decrease the response speedsetting value in correspondence to the second frame rate.

The processor is further configured to adjust the response speed settingvalue of the display panel by adjusting at least one of a dynamiccapacitance compensation (DCC) value for compensating for a responsespeed of the display panel or a liquid crystal charging timing of thedisplay panel.

BRIEF DESCRIPTION OF THE DRAWINGS

The above and other aspects, features, and advantages of certainembodiments of the present disclosure will be more apparent from thefollowing description taken in conjunction with the accompanyingdrawings, in which:

FIG. 1 is a schematic block diagram illustrating components of a displayapparatus according to an embodiment;

FIGS. 2A and 2B are views illustrating a frame rate of a display panelaccording to an embodiment;

FIGS. 3A and 3B are views illustrating a frame rate of a display panelaccording to an embodiment;

FIG. 4 is a flowchart of a control method of a display apparatusaccording to an embodiment;

FIG. 5 is a view illustrating changing a frame rate according to anembodiment;

FIG. 6 is a view illustrating a UI according to an embodiment;

FIG. 7 is a view illustrating fixing a frame rate according to anembodiment;

FIG. 8 is a view illustrating generating a frame according to anembodiment;

FIG. 9 is a view illustrating generating a frame according to anembodiment; and

FIG. 10 is a block diagram illustrating components of the displayapparatus according to an embodiment.

DETAILED DESCRIPTION

Certain embodiments will be described in detail with reference to theaccompanying drawings.

General terms that are currently widely used were selected as terms usedin embodiments in consideration of functions, but may be changeddepending on the intention of those skilled in the art or a judicialprecedent, the emergence of a new technique, and the like. In addition,in a specific case, terms arbitrarily chosen by an applicant may exist.In this case, the meaning of such terms will be mentioned in detail in acorresponding description portion. Therefore, the terms used inembodiments are to be defined based on the meaning of the terms and thecontents throughout the description rather than simple names of theterms.

As used herein, an expression “have”, “may have”, “include”, “mayinclude”, or the like, may indicate existence of a corresponding feature(for example, a numerical value, a function, an operation, a componentsuch as a part, or the like), and does not exclude existence of anadditional feature.

An expression “at least one of A and/or B” is to be understood torepresent “A” or “B” or “any one of A and B”.

As used herein, the terms “1st” or “first”, “2nd” or “second”, or thelike, may use corresponding components regardless of importance or orderand are used to distinguish one component from another, without limitingthe components.

When it is mentioned that any component (for example, a first component)is (operatively or communicatively) coupled with/to or is connected toanother component (for example, a second component), it is to beunderstood that any component is directly coupled to another componentor may be coupled to another component through the other component (forexample, a third component).

Singular forms are intended to include plural forms unless the contextclearly indicates otherwise. It will be further understood that terms“include” or “formed of” used herein specify the presence of features,numerals, steps, operations, components, parts, or combinations thereof,but do not preclude the presence or addition of one or more otherfeatures, numerals, steps, operations, components, parts, orcombinations thereof.

As used herein, a “module” or a “—er/or” may perform at least onefunction or operation, and be implemented by hardware or software or beimplemented by a combination of hardware and software. In addition, aplurality of “modules” or a plurality of “—ers/—ors” may be integratedin at least one module and be implemented by at least one processorexcept for a “module” or a “—er/or” that needs to be implemented byspecific hardware.

As used herein, a term “user” may refer to a person using an electronicapparatus or an apparatus (for example, an artificial intelligenceelectronic apparatus) using an electronic apparatus.

Hereinafter, an embodiment will be described in detail with reference tothe accompanying drawings.

FIG. 1 is a schematic block diagram illustrating components of a displayapparatus according to an embodiment.

As illustrated in FIG. 1 , a display apparatus 100 according to anembodiment includes a communication interface 110, a display panel 120,and a processor 130.

Here, the display apparatus 100 displays video data. The displayapparatus 100 may be implemented by a television (TV), but is notlimited thereto, and may be any apparatus having a display function,such as a video wall, a large format display (LFD), a digital signage, adigital information display (DID), a projector display, or the like. Thedisplay apparatus 100 may be implemented by displays having variousforms such as a liquid crystal display (LCD), an organic light emittingdiode (OLED), a liquid crystal on silicon (LCoS), a digital lightprocessing (DLP), a quantum dot (QD) display panel, a quantum dot LED(QLED), a micro LED (μLED), a mini LED, and the like. Meanwhile, thedisplay apparatus 100 may also be implemented by a touch screen combinedwith a touch sensor, a flexible display, a rollable display, athree-dimensional (3D) display, and a display in which a plurality ofdisplay modules are physically connected to each other, or the like.

The communication interface 110 including a circuit according to anembodiment receives various types of videos. For example, thecommunication interface 110 may receive a video signal in a streaming ordownload manner from an external apparatus (for example, a sourceapparatus), an external storage medium (for example, a universal serialbus (USB) memory), an external server (for example, a Web hard), or thelike, through a communication manner such as access point (AP)-basedWi-Fi (Wireless local area network (LAN)), Bluetooth, Zigbee,wired/wireless LAN, wide area network (WAN), Ethernet, IEEE 1394,high-definition multimedia interface (HDMI), USB, mobile high-definitionlink (MHL), audio engineering society/European broadcasting union(AES/EBU), an optical manner, a coaxial manner, or the like. Here, thevideo signal may be any one digital video signal of a standarddefinition (SD), high definition (HD), full HD, or ultra HD video, butis not limited thereto.

Particularly, the communication interface 110 according to an embodimentmay receive a video from the external apparatus. For example, thedisplay apparatus 100 may sequentially receive a plurality of videoframes configuring a video through the communication interface 110.

However, this is an example, embodiments are not limited thereto. As anexample, the display apparatus 100 may store a video received throughthe communication interface 110 in a memory, load the video from thememory, and provide the video through the display panel 120. As anotherexample, the display apparatus 100 may load a video pre-stored in thememory and provide the video through the display panel 120.

The display panel 120 according to an embodiment may be selectivelydriven at any one of a plurality of frame rates. Here, the frame ratemay refer to a speed at which the display apparatus 100 displays oneframe. The frame rate of the display panel 120 may be referred to as arefresh rate, a frequency, or a scan rate, but hereinafter, will bereferred to as a frame rate for convenience of explanation. The framerate of the display panel 120 may be represented by Hz. As an example,when the frame rate of the display panel 120 is 60 Hz, the display panel120 may provide 60 frames per second. As another example, when the framerate of the display panel 120 is 120 Hz, the display panel 120 mayprovide 120 frames per second. Here, an example in which the displaypanel 120 is driven at the frame rate of 60 Hz or 120 Hz is only anexample, embodiments are not limited thereto. For example, the displaypanel 120 may be driven at various frame rates such as 75 Hz, 144 Hz,and 240 Hz.

The display panel 120 according to an embodiment may be driven at anyone of the plurality of frame rates according to the control of theprocessor 130. Hereinafter, embodiments in which the processor 130selects any one of the plurality of frame rates, drives the displaypanel 120 at the selected frame rate, and outputs a video receivedthrough the communication interface 110 will be described.

The processor 130 controls a general operation of the display apparatus100.

According to an embodiment, the processor 130 may be implemented by adigital signal processor (DSP), a microprocessor, an artificialintelligence (AI) processor, or a time controller (T-CON) processing adigital video signal. However, the processor 130 is not limited thereto,but may include one or more of a central processing unit (CPU), a microcontroller unit (MCU), a micro processing unit (MPU), a controller, anapplication processor (AP), a communication processor (CP), and an ARMprocessor, or may be defined by these terms. In addition, the processor130 may be implemented by a system-on-chip (SoC) or a large scaleintegration (LSI) in which a processing algorithm is embedded or may beimplemented in a field programmable gate array (FPGA) form.

When the video is received through the communication interface 110, theprocessor 130 according to an embodiment may identify a frame rate ofthe received video.

As an example, the video (for example, a moving picture) is a set oftemporally continuous still images, and one still image may be a frame.The frame rate of the video may be represented by frames per second(fps). That is, the frame rate of the video may refer to the number offrames configuring the video for 1 second. The frame rate of the videomay be referred to as a frame speed and a frame ratio, but hereinafter,will be referred to as a frame rate for convenience of explanation.

For example, if a video of at least 24 fps or more is provided, a usermay determine that the video is a smooth and seamless video. Generally,as the frame rate of the video increases, the user feels that the smoothand seamless video is provided, but is not limited thereto.

The display apparatus 100 according to an embodiment may receive anddisplay videos of various frame rates such as 60 fps, 120 fps, 1000 fps,and the like, such as a game video (for example, a first-person shooter(FPS) game, a racing game), a sports video, and a slow motion video.

When the video is received through the communication interface 110, theprocessor 130 according to an embodiment may identify the frame rate ofthe received video. As an example, the processor 130 may identify theframe rate of the video (for example, fps of the video) based onmetadata of the received video. Meanwhile, a configuration in which theprocessor 130 identifies the frame rate of the video based on themetadata of the video is only an example, and the disclosure is notnecessarily limited thereto. As an example, the processor 130 may alsoidentify the frame rate of the video based on the number of framesconfiguring the video for 1 second among a plurality of framesconfiguring the video.

Then, in a case where the processor 130 drives the display panel 120 ata frame rate corresponding the frame rate identified based on thereceived video, the processor 130 may adjust a setting value of thedisplay panel so that the display panel operates at the frame rate (thatis, the identified frame rate) of the video among the plurality of framerates at which that the display panel 120 may be driven. As an example,when the frame rate of the video is 60 fps, the processor 130 may adjustthe setting value of the display panel 120 so that the display panel 120operates at 60 Hz corresponding to 60 fps. As another example, when theframe rate of the video is 120 fps, the processor 130 may adjust thesetting value of the display panel 120 so that the display panel 120operates at 120 Hz corresponding to 120 fps.

Here, the frame rate (for example, fps unit) of the video may refer tothe number of frames configuring the video for 1 second, and the framerate (for example, Hz unit) of the display panel 120 may refer to thenumber of frames provided by the panel 120 for 1 second.

As an example, when the frame rate of the video is lower than that ofthe display panel 120, some of the frames of the video of the displaypanel 120 are repeatedly displayed, and thus, there is a problem thatthe video appears slow to the user.

As another example, when the frame rate of the video is higher than thatof the display panel 120, several new frames are generated before thedisplay panel 120 displays the next frame, and a problem that someframes are lost or are not displayed may thus occur.

When the frame rate of the video is much higher than that of the displaypanel 120, the next frame is input in a cycle in which the display panel120 has displayed a specific frame, such that screen tearing in whichdifferent frames are displayed on upper and lower portions of a screenmay occur. Therefore, the display apparatus 100 according to anembodiment may perform vertical synchronization (V-sync) for setting aframe generation timing of the video and a frame output timing of thedisplay panel 120 to be synchronized.

On the other hand, a display apparatus 100 according to the related artperforms a process in which a frame passes through a verticalsynchronization buffer to synchronize a generation timing of a frameconfiguring an input video and a frame output timing of the displaypanel 120, and has a problem that a delay time is generated in such aprocess. As a result, there was a problem that a delay occurs betweeninput and output of the video.

For example, assuming that the received video is a 60 fps video, theprocessor 130 may perform calculation on the received video whilewaiting for vertical synchronization in units of 1/60 s (16.6 ms). Whenthe display panel 120 operates at a frame rate of 120 Hz, there is aproblem that a delay of at least 8.3 ms (16.6 ms/2) occurs until theprocessor 130 performs calculation on the received video and outputs thevideo through the display panel 120. The delay may be referred to as alatency, an input lag, a display lag, and the like.

The processor 130 according to an embodiment may adjust the settingvalue of the display panel 120 so that the display panel 120 operates ata frame rate (for example, a scan rate) corresponding to the frame rateof the video. Then, the processor 130 may control the display panel 120to output the received video. In this case, the delay occurrence betweenvideo outputs may be minimized.

A detailed description therefor will be provided with reference to FIGS.2A to 3B.

FIGS. 2A and 2B are views illustrating a frame rate of a display panelaccording to an embodiment.

Referring to FIGS. 2A and 2B, according to an embodiment, the processor130 identifies a frame rate of a received video 10 including a firstframe 10-1 and second to n-th frames 10-2 to 10-n, e.g., the processor130 identifies an input frame rate of the input frames. When the framerate of the received video 10 is a first frame rate, the processor 130may adjust a setting value of the display panel 120 to output an outputvideo 20 so that the display panel 120 operates at a frame rate (forexample, a scan rate) corresponding to the first frame rate. The outputvideo 20 may include a first output frame 20-1 and second to n-th outputframes 20-2 to which correspond to the input frames of the receivedvideo 10.

For example, the processor 130 may adjust at least one of a DCC valuefor compensating for a response speed of the display panel 120 or aliquid crystal charging timing or luminance of the display panel 120,included in the setting value, based on the identified first frame rate.

Here, DCC is a method of comparing a gradation value of a previous framewith a gradation value of a current frame for an arbitrary pixel andperforming processing of RGB data so that a value greater than adifference between these gradation values is added to the gradationvalue of the previous frame. Generally, a delay (for example, aduration) of one frame is 16.7 ms. When a voltage is applied across aliquid crystal material in an arbitrary pixel, it takes time for theliquid crystal material to respond to the voltage. Therefore, a timedelay is inevitable to represent an intended gradation value. A DCCfunction is a technology for minimizing this time delay. For example,when the gradation value in the previous frame is ‘118’ and thegradation value in the current frame is ‘128’ for the arbitrary pixel, avalue obtained by adding a value (referred to as a compensation value)greater than ‘10’, which is a difference between two gradation values,to the gradation value in the previous frame, for example, ‘135’ isconverted as the gradation value of the current frame. In this DCCmethod, a frame memory for storing data of the previous frame isrequired, and the compensation value may be determined by a look-uptable created based on the data of the previous frame and data of thecurrent frame. The processor 130 may also obtain the DCC value based onvarious equations for calculating the compensation value, in addition tothe lookup table.

Then, the processor 130 may adjust the setting value of the displaypanel 120 according to the obtained DCC value to operate the displaypanel 120 at a specific frame rate.

Referring to FIGS. 2A and 2B, when the frame rate of the received video10 is 60 fps, the processor 130 may operate the display panel 120 at aframe rate (for example, a scan rate) of 60 Hz corresponding to 60 fps.In this case, a first output frame 20-1 corresponding to a first frame10-1 configuring the input video may be obtained without a delay (forexample, about 16.6 ms) required for calculation of the first frame10-1.

FIGS. 3A and 3B are views illustrating a frame rate of a display panelaccording to an embodiment.

Referring to FIGS. 3A and 3B, according to an embodiment, the processor130 identifies a frame rate of a received video 10. When the frame rateof the received video 10 is a second frame rate, the processor 130 mayadjust a setting value of the display panel 120 so that the displaypanel 120 operates at a frame rate (for example, a scan rate)corresponding to the second frame rate. According to an embodiment, thesecond frame rate may be a frame rate having a frequency higher thanthat of the first frame rate. For example, the first frame rate may be60 Hz (or 60 fps), and the second frame rate may be 120 Hz (or 120 fps).

Then, the processor 130 may adjust at least one of a DCC value forcompensating for a response speed of the display panel 120 or a liquidcrystal charging timing or luminance of the display panel 120, includedin the setting value, based on the identified second frame rate.

Referring to FIGS. 3A and 3B, when the frame rate of the received video10 is 120 fps, the processor 130 may operate the display panel 120 at aframe rate (for example, a scan rate) of 120 Hz corresponding to 120fps. In this case, a first output frame 20-1 corresponding to a firstframe 10-1 configuring the input video may be obtained without a delay(for example, about 8.3 ms (1 s/120) required for calculation of thefirst frame 10-1. That is, the processor 130 may provide an output video20 corresponding to the received video 10 through the display panel 120without a delay time required for calculation or verticalsynchronization for the received video 10.

According to an embodiment, the DCC value and the liquid crystalcharging timing included in the setting value corresponding to the firstframe rate (for example, 60 Hz) may be greater than the DCC value andthe liquid crystal charging timing included in the setting valuecorresponding to the second frame rate (for example, 120 Hz).

For example, in a case where the display panel 120 is driven at a framerate of 120 Hz, 120 frames need to be provided for 1 second, and the DCCvalue and the liquid crystal charging timing for compensating for aresponse speed may thus be reduced as compared with a case where thedisplay panel 120 is driven at a frame rate of 60 Hz.

Then, the processor 130 may adjust the setting value of the displaypanel 120 according to the obtained DCC value to operate the displaypanel 120 at a specific frame rate.

The processor 130 according to an embodiment may adjust the luminance ofthe display panel 120 so that a gamma value of the display panel 120 ismaintained as a reference gamma value even though the frame rate of thedisplay panel 120 is changed.

For example, when the frame rate identified according to the receivedvideo 10 is changed from the second frame rate (for example, 120 Hz) tothe first frame rate (for example, 60 Hz), the processor 130 may drivethe display panel 120 at the first frame rate by increasing at least oneof the DCC value or the liquid crystal charging timing based on thesetting value corresponding to the frame rate. Then, the processor 130may adjust the luminance or brightness of the display panel 120 so thata changed gamma value is maintained as the reference gamma value (forexample, 2.2 gamma value) as at least one of the DCC value or the liquidcrystal charging timing is increased.

FIG. 4 is a flowchart of a control method of a display apparatusaccording to an embodiment.

Referring to FIG. 4 , in a control method of a display apparatusincluding a display panel that may be driven at a plurality of framerates, when a video is received, a frame rate of the received video isidentified (operation S510).

Then, the setting value of the display panel is adjusted so that thedisplay panel operates at the identified frame rate of the plurality offrame rates (operation S520).

Then, the display panel is controlled to output the received video(operation S530).

Operation S520 of adjusting the setting value according to an embodimentmay include adjusting at least one of a DCC value for compensating for aresponse speed of the display panel or a liquid crystal charging timingor luminance of the display panel, included in the setting value, basedon the identified frame rate.

Here, the plurality of frame rates may include a first frame rate and asecond frame rate having a frequency higher than that of the first framerate, and a DCC value and a liquid crystal charging timing included in asetting value corresponding to the first frame rate may be greater thana DCC value and a liquid crystal charging timing included in a settingvalue corresponding to the second frame rate.

The plurality of frame rates may include a first frame rate and a secondframe rate having a frequency higher than that of the first frame rate,and operation S520 of adjusting the setting value may include increasingthe DCC value and the liquid crystal charging timing based on thesetting value corresponding to the first frame rate when the identifiedframe rate is changed from the second frame rate to the first framerate, and adjusting the luminance of the display panel so that a gammavalue of the display panel is maintained as a reference gamma value.

In addition, the control method according to an embodiment may furtherinclude identifying whether or not to change the frame rate of thedisplay panel based on a user command and operation S530 of controllingthe display panel may include controlling the display panel to outputthe adjusted video by adjusting the frame configuring the received videowhen the user command is a command to fix the frame rate of the displaypanel and the identified frame rate corresponding to the received videoand the fixed frame rate of the display panel that are different fromeach other.

The plurality of frame rates may include a first frame rate and a secondframe rate having a frequency higher than that of the first frame rate,and operation S530 of controlling the display panel may includegenerating a new frame between a plurality of frames configuring thereceived video when the identified frame rate is the first frame rateand the fixed frame rate is the second frame rate, and controlling thedisplay panel to output an adjusted video corresponding to the receivedvideo including the plurality of frames and the new frame.

In addition, the new frame may include at least one of a frame generatedby repeating each of the plurality of frames configuring the receivedvideo or a frame generated based on at least two frames of the pluralityof frames configuring the received video.

Here, the frame generated based on at least two frames of the pluralityof frames configuring the received video may be a frame generated basedon motion information of an object included in at least two frames.

In addition, the control method according to an embodiment may furtherinclude identifying whether or not to change the frame rate of thedisplay panel based on a user command for controlling whether or not tochange the frame rate of the display panel when the user command isreceived, and operation S520 of adjusting the setting value of thedisplay panel may include changing the frame rate to the identifiedframe rate when the user command is a command to change the frame rateof the display panel and the identified frame rate corresponding to thereceived video and the frame rate of the display panel that aredifferent from each other.

In addition, operation S520 of adjusting the setting value of thedisplay panel may include changing the frame rate of the display panelbased on a user command for changing the frame rate of the display panelwhen the user command is received.

The control method according to an embodiment may further includedisplaying a user interface (UI) for changing the frame rate of thedisplay panel, and operation S520 of adjusting the setting value of thedisplay panel may include adjusting the setting value of the displaypanel so that the display panel operates at a frame rate correspondingto a user command input through the UI.

In addition, operation S510 of identifying the frame rate of thereceived video may include identifying the frame rate of the receivedvideo based on the metadata of the received video, and operation S520 ofadjusting the setting value of the display panel may include adjustingthe setting value of the display panel so that the display paneloperates at the identified frame rate.

In addition, the control method according to an embodiment may furtherinclude analyzing the received video to obtain video processing delayinformation related to processing of the received video, operation S510of identifying the frame rate of the received video may further includeidentifying the frame rate of the received video based on the videoprocessing delay information, and operation S520 of adjusting thesetting value of the display panel may further include adjusting thesetting value of the display panel so that the display panel operates atthe identified frame rate.

Meanwhile, the identifying of whether or not to change the frame rate ofthe display panel 120 based on the user command will hereinafter bedescribed with reference to FIGS. 5 and 6 .

FIG. 5 is a view illustrating changing a frame rate according to anembodiment.

Referring to FIG. 5 , the processor 130 according to an embodimentidentifies the frame rate of the video (for example, fps of the video)(operation S610) when the video is received.

Then, the processor 130 identifies whether or not to change the framerate of the display panel 120 based on the user command for controllingwhether or not to change the frame rate of the display panel 120(operation S620).

When the user command is a command to change the frame rate (operationS620: Y), the processor 130 identifies whether or not the identifiedframe rate corresponding to the received video and the frame rate of thedisplay panel 120 are different from each other (operation S630).

Then, when the identified frame rate corresponding to the received videoand the frame rate of the display panel 120 are different from eachother (operation S630: Y), the processor 130 may change the frame rateof the display panel 120 to the identified frame rate (operation S640).Then, the processor 130 controls the display panel 120 to output thereceived video (operation S650).

As another example, when the identified frame rate corresponding to thereceived video and the frame rate of the display panel 120 are the same(operation S630: N), the processor 130 controls the display panel tooutput the received video (operation S650). That is, the processor 130may control the display panel 120 to output the received video withoutchanging the frame rate of the display panel 120.

According to an embodiment, the processor 130 may also identify whetherto change the frame rate of the display panel 120 and then output thevideo or to generate a new frame (for example, an interpolation frame)in the video to adjust the frame rate of the video to correspond to theframe rate of the display panel 120, and then output an adjusted video,based on metadata corresponding to the video, in addition to the usercommand.

As an example, the processor 130 may identify the frame rate of thereceived video based on the metadata of the received video. For example,the metadata may include information on whether the frame rate of thevideo corresponds to 60 Hz, 120 Hz, or 144 Hz. The processor 130 mayadjust the setting value of the display panel 120 to operate the displaypanel 120 at the frame rate identified based on the metadata.

As another example, the metadata may include information on whether ornot to change the frame rate of the display panel 120 to coincide withthe frame rate of the video and then output the corresponding video. Forexample, the processor 130 may change the frame rate of the displaypanel 120 to coincide with the frame rate of the video based on theinformation included in the metadata, and then output the correspondingvideo. As another example, the processor 130 may generate a new frame(for example, an interpolation frame) in the video to adjust the framerate of the video to correspond to the frame rate of the display panel120, and then output the adjusted video, without changing the frame rateof the display panel 120, based on the information included in themetadata.

According to an embodiment, when the user command for changing the framerate of the display panel 120 is received, the processor 130 may changethe frame rate of the display panel 120 based on the user command.

This will be described in detail with reference to FIG. 6 .

FIG. 6 is a view illustrating a UI according to an embodiment.

The processor 130 according to an embodiment identifies the frame rateof the video (for example, fps of the video) when the video is received.

Then, the processor 130 may identify the frame rate corresponding to theuser command for changing the frame rate of the display panel 120. Then,the processor 130 may change the frame rate of the display panel 120.

As an example, the processor 130 may display a UI for changing the framerate of the display panel 120. Referring to FIG. 6 , the processor 130may control the display panel 120 to display a UI through which each ofa plurality of frame rates at which the display panel 120 may be drivenmay be selected.

When a user command for selecting one of the plurality of frame rates isreceived, the processor 130 may identify a frame rate corresponding tothe user command. Then, the processor 130 may adjust a setting value ofthe display panel so that the display panel operates at a frame ratecorresponding to the user command input through the UI.

FIG. 6 illustrates 60 Hz and 120 Hz as an example of the plurality offrame rates for convenience of explanation, but the plurality of framerates are not limited thereto.

FIG. 7 is a view illustrating fixing a frame rate according to anembodiment.

Referring to FIG. 7 , as described above with reference to FIG. 5 , inoperation S620, when the user command regarding a change of the framerate is received, the processor 130 identifies whether or not to changethe frame rate of the display panel 120 based on the user command. Whenthe user command is a command to change the frame rate (operation S620:Y), the processor 130 identifies whether or not the identified framerate corresponding to the received video and the frame rate of thedisplay panel 120 are different from each other (operation S660).

When the identified frame rate corresponding to the received video andthe frame rate of the display panel 120 are different from each other(operation S660: Y), the processor 130 may adjust frames configuring thereceived video and control the display panel to output the adjustedvideo (operation S670).

When the identified frame rate corresponding to the received video andthe frame rate of the display panel 120 are the same (operation S660:N), the processor 130 may control the display panel 120 to output thereceived video (operation S680).

Hereinafter, embodiments in which the processor 130 adjusts framesconfiguring a received video and controls the display panel to output anadjusted video in a case where a user command is a command to fix aframe rate and an identified frame rate corresponding to the receivedvideo and a frame rate of the display panel 120 are different from eachother will be described.

FIG. 8 is a view illustrating generating a frame according to anembodiment.

Referring to FIG. 8 , the processor 130 according to an embodiment maygenerate a new frame between a plurality of frames configuring areceived video 10 when a frame rate corresponding to the received video10 is a first frame rate (for example, 60 fps) and a frame rate of thedisplay panel 120 fixed according to a user command is a second framerate (for example, 120 Hz). Here, the generated new frame may bereferred to as an interpolation frame.

The processor 130 may control the display panel 120 to output anadjusted video 20 including the plurality of frames configuring thereceived video 10 and the generated new frame and corresponding to thereceived video 10.

According to an embodiment, the processor 130 may obtain the new frame,that is, the interpolation frame, based on various frame interpolationtechnologies according to the related art.

Referring to FIG. 8 , the processor 130 according to an embodiment mayobtain the new frame by repeating the previous frame between therespective frames configuring the received video 10. As an example, whena frame rate of the received video 10 is 60 fps, the processor 130according to an embodiment may obtain the adjusted video 20 of 120 fpsby repeating each of the plurality of frames configuring the video 10.Then, the processor 130 may control the display panel 120 to display theadjusted video 20. Meanwhile, specific numbers are only examples, and anembodiment is not limited thereto. For example, when a frame rate of thereceived video 10 is 30 fps, the processor 130 according to anembodiment may obtain the adjusted video 20 of 60 fps or 120 fps byrepeating each of the plurality of frames configuring the video 10 basedon the frame rate of the display panel 120.

In the above-described method of obtaining the new frame, that is, theinterpolation frame by repeating each of the frames configuring thevideo 10 is described. For example, the processor 130 may control thedisplay panel 120 to repeatedly provide a first output frame 20-1 of theadjusted video 20 corresponding to a first frame 10-1 of the receivedvideo 10. However, the method of obtaining the new frame by repeatingthe frame as described above is only an example, and the processor 130may obtain the new frame and the adjusted video 20 including the newframe by various methods.

FIG. 9 is a view illustrating generating a frame according to anembodiment.

Referring to FIG. 9 , the processor 130 may generate a new frame basedon at least two of a plurality of frames configuring a received video10. Here, the generated frame may be a frame generated based on motioninformation of an object included in at least two of the plurality offrames configuring the video 10.

As an example, the processor 130 may obtain a new output frame 20-1′based on a first frame 10-1 and a second frame 10-2 of the plurality offrames configuring the received video 10. Here, the new output frame20-1′ might not be the same as a first output frame 20-1 correspondingto the first frame 10-1 or a second output frame 20-2 corresponding tothe second frame 10-2.

Here, the new output frame 20-1 may be a frame obtained by calculationbased on motion information of an object included in each of the firstframe 10-1 and the second frame 10-2. Here, the motion information mayinclude a position of an object in a frame, a position and a form of theobject in the previous frame, change amounts in a position and a form ofthe object in the next frame, and the like.

The processor 130 according to an embodiment may position the new outputframe 20-1′ between the first output frame 20-1 and the second outputframe 20-2 within an adjusted video, and output the new output frame20-1′ after the previous frame (for example, the first output frame20-1) is output and before the next frame (for example, the secondoutput frame 20-2) is output. Meanwhile, as a method of obtaining thenew frame according to an embodiment, various methods according to therelated art such as fluid motion of AMD, Inc., and the like, may beused, in addition to the method described above.

FIG. 10 is a block diagram illustrating components of the displayapparatus according to an embodiment in detail.

Referring to FIG. 10 , the display apparatus 100 according to anembodiment may include the communication interface 110, the displaypanel 120, the processor 130, a panel driver 140, a memory 150 and auser Interface 160. However, the display apparatus 100 does notnecessarily include all of the components described above. In addition,the display apparatus 100 may further include components such as anaudio outputter, a power supply, and the like.

The display panel 120 may include a liquid crystal layer, a pixelelectrode, a liquid crystal capacitor, a gate line, a data line, abacklight unit, and the like. The display panel 120 may expressbrightness of each pixel according to a luminance value identifiedthrough luminance information.

The processor 130 according to an embodiment may analyze the receivedvideo to obtain video processing delay information related to theprocessing of the received video, and identify the frame rate of thereceived video based on the video processing delay information, andadjust the setting value of the display panel so that the display paneloperates at the identified frame rate.

The processor 130 according to an embodiment may perform at least onevideo correction processing on the received video, and then provide thevideo through the display panel 120. In this case, there is a risk thatan input delay time and an input lag will occur depending on a timerequired from reception of the video until output of the video.

The processor 130 according to an embodiment may obtain video processingdelay information related to processing (for example, video correctionprocessing according the related art) of the received video. Then, theprocessor 130 may identify the frame rate of the video based on thevideo processing delay information. For example, the processor 130 mayincrease the frame rate of the display panel 120 in a case where a timerequired until the output of the received video exceeds a threshold timebased on the video processing delay information. As an example, theprocessor 130 may increase the frame rate of the display panel 120 from60 Hz to 120 Hz and output the received video.

Here, the video processing delay information may be determined based onat least one of type information of the received video, user interactionrelated information, or object information in the received video. Forexample, the type information of the video may include information onwhether or not the received video corresponds to any one of moviecontents, game contents, streaming contents, or image contents. However,the contents described above are only examples, and an embodiment is notlimited thereto. For example, the type information of the video mayinclude content type information classified in more detail. As anexample, the type information of the video may include information onwhich genre in a game, such as a rhythm game, an FPS game, a fightinggame, or the like, among the game contents the received videocorresponds to. As another example, the type information of the videomay include information on which genre in a movie, such as an actionmovie, a war movie, a science fiction movie, an animation, or the like,among the movie contents the received video corresponds to.

When it is identified that the received video is an FPS game content,the processor 130 according to an embodiment may obtain a delay time,that is, video processing delay information. Then, the processor 130 maychange the frame rate of the display panel 120 when the delay timeexceeds a threshold time based on the video processing delayinformation. For example, the processor 130 may increase the frame rateof the display panel 120 from 60 Hz to 120 Hz. For example, when it isidentified that the delay time exceeds 100 ms based on the videoprocessing delay information, the processor 130 may change the framerate of the display panel 120 for a game to be smoothly played by theuser.

As another example, when it is identified that the received video is arhythm game content, the processor 130 may obtain a delay time, that is,video processing delay information. Then, the processor 130 may changethe frame rate of the display panel 120 when it is identified that thedelay time exceeds a threshold time, for example, 50 ms based on thevideo processing delay information. In the embodiment described above,specific numbers are only examples for convenience of explanation, andan embodiment is not limited thereto. For example, the processor 130 mayreceive the video processing delay information from an external serverthrough the communication interface, identify whether or not to changethe frame rate of the display panel 120 based on information onthreshold times mapped to each of information on video types included inthe received video processing delay information, and to what extent (forexample, 120 Hz, 144 Hz, or the like) to change the frame rate.

As another example, the processor 130 may identify type information ofthe video, and identify a frame rate corresponding to the identifiedtype information. Then, the processor 130 may drive the display panel120 at the identified frame rate. For example, in a case of the FPS gamecontent among the game contents, the display panel 120 may be set to bedriven at 144 Hz, and the processor 130 may change the frame rate of thedisplay panel 120 to 144 Hz when it is identified that the receivedvideo is the FPS game content through metadata of the received video oranalysis of the received video. However, this is an example, andspecific frame rates may be set for each of a plurality of contentgenres or specific frame rates may be set for only some content genres.For example, when a specific frame rate corresponding to a content genreof the received video is set, the processor 130 may drive the displaypanel 120 at the set frame rate, and when a specific frame rate is notset for a content genre of the received video, the processor 130 maydrive the display panel 120 at a frame rate obtained based on metadataof the received video.

The processor 130 according to an embodiment may determine the videoprocessing delay information based on object information in the video.

As an example, in a case where objects of whose number is a thresholdnumber or more are identified within the received video or in a casewhere it is identified that a plurality of objects are changed withinthe video according to object movement information, the processor 130may change the frame rate of the display panel 120 to smoothly providethe objects to the user. For example, in a case where an object in aframe included in the received video is rapidly changed or in a casewhere a plurality of objects are moved, the processor 130 may increasethe frame rate of the display panel 120 to provide a smooth video to theuser without a lag and a delay, and output the received video. Here, theobject movement information may include information on a position changeof each of objects included in the previous frame and a current frame,or the like.

For example, in a case where a content in which positions of each of theplurality of objects are changed when a frame is changed, such as ashooting game content, a sports game content, or the like, isidentified, the processor 130 may change the frame rate of the displaypanel 120 to a threshold frame rate or more, and output the video (orthe content). Here, the threshold frame rate may refer to a frame ratefor providing game contents, movie contents, or the like, to the userwithout a delay. For example, the threshold frame rate may be set to 120Hz, but is not limited thereto.

As another example, the processor 130 may determine the video processingdelay information based on the user interaction related information. Forexample, when it is identified that a user's interaction is inputthreshold times or more based on the user interaction relatedinformation, the processor 130 may change the frame rate of the displaypanel 120. Here, the user interaction related information may include auser's input, a screen manipulation command, a manipulation command foran object in the game contents in a case of the game contents, and thelike. For example, in a case where the user's interaction is inputthreshold times or more, the processor 130 may increase the frame rateof the display panel 120 to smoothly provide a screen in which aplurality of interactions are reflected to the user.

As another example, in a case where fine adjustment of a specific objectin the video is required based on the user interaction relatedinformation, the processor 130 may increase the frame rate of thedisplay panel 120 so that afterimage or an overlay is not generated. Forexample, when a user interaction with a specific object such as atarget, or the like, in the shooting game content is received and it isidentified that the specific object is an object requiring fineadjustment, the processor 130 may increase the frame rate of the displaypanel 120 to minimize occurrence of the delay.

The panel driver 140 may provide a driving signal to the display panel120. For example, the panel driver 140 may include a gate driver, a datadriver, a gradation voltage generator, and a signal controller. Althoughthe panel driver 140 is described as a separate component in theembodiment of FIG. 10 , in an embodiment, the processor 130 may alsoserve as the panel driver 140. As an example, the panel driver 140 maydrive the display panel 120 at a frame rate corresponding to the framerate of the received video 10 based on the frame rate of the receivedvideo 10.

The memory 150 may be electrically connected to the processor 130 andmay store data used according to embodiments. For example, the memory150 may be implemented as an internal memory such as a read-only memory(ROM) (for example, an electrically erasable programmable read-onlymemory (EEPROM)), a random access memory (RAM), or the like, included inthe processor 130 or be implemented as a memory separate from theprocessor 130.

The memory 150 may be implemented in a form of a memory embedded in thedisplay apparatus 100 or be implemented in a form of a memory attachableto and detachable from the display apparatus 100, depending on a datastoring purpose. For example, data for driving the display apparatus 100may be stored in the memory embedded in the display apparatus 100, anddata for an extension function of the display apparatus 100 may bestored in the memory attachable to and detachable from the displayapparatus 100. In a case where the memory 150 is implemented as thememory embedded in the display apparatus 100, the memory 150 may be atleast one of a volatile memory (for example, a dynamic random accessmemory (DRAM), a static RAM (SRAM), a synchronous dynamic RAM (SDRAM),or the like) or a non-volatile memory (for example, a onetimeprogrammable read-only memory (OTPROM), a programmable ROM (PROM), anerasable programmable ROM (EPROM), an electrically erasable andprogrammable ROM (EEPROM), a mask ROM, a flash ROM, a flash memory (forexample, a NAND flash, a NOR flash, or the like), a hard drive, or asolid state drive (SSD)).

In a case where the memory 150 is implemented as the memory attachableto and detachable from the display apparatus 100, the memory 150 may bea memory card (for example, a compact flash (CF), a secure digital (SD),a micro-SD, a mini-SD, an extreme digital (xD), a multi-media card(MMC), or the like), an external memory (for example, a USB memory)connectable to a USB port, or the like.

In particular, the memory 150 according to an embodiment may storeinformation on a setting value required for the display panel 120 to bedriven at a specific frame rate of a plurality of frame rates. Forexample, the memory 150 may store a setting value (for example, at leastone of a DCC value, a liquid crystal charging timing, or luminance)required for the display panel 120 to be driven at a frame rate of 60Hz. In addition, the memory 150 may store a setting value (for example,at least one of a DCC value, a liquid crystal charging timing, orluminance) required for the display panel 120 to be driven at a framerate of 120 Hz. The information on the setting value may be in a look-uptable form, but is not necessarily limited thereto. The information onthe setting value may be stored in the memory 150 inside the displayapparatus 100 or luminance information stored in an external server maybe used. In this case, the communication interface 110 may communicatewith the external server to receive the information on the settingvalue.

The user interface 160 may be implemented by a device such as a button,a touch pad, a mouse, and a keyboard or may be implemented by a touchscreen, a remote control transmitter/receiver, or the like, capable ofperforming both of the display function described above and amanipulation input function. The remote control transmitter/receiver mayreceive a remote control signal from an external remote control deviceor transmit a remote control signal to the external remote controldevice through at least one of infrared communication, Bluetoothcommunication, or Wi-Fi communication.

An outputter outputs a sound signal. For example, the outputter mayconvert a digital sound signal processed by the processor 130 into ananalog sound signal, and amplify and output the analog sound signal. Forexample, the outputter may include at least one speaker unit capable ofoutputting at least one channel, a D/A converter, an audio amplifier,and the like. According to an example, the outputter may be implementedto output various multi-channel sound signals. In this case, theprocessor 130 may control the outputter to enhancement-process an inputsound signal to correspond to enhancement processing of the input videoand then output the sound signal. For example, the processor 130 mayconverts an input 2-channel sound signal into a virtual multi-channel(for example, 5.1-channel) sound signal, recognize a position where thedisplay apparatus 100 is put and process the input 2-channel soundsignal as a stereoscopic sound signal optimized for a space, or providean optimized sound signal according to a type (for example, a contentgenre) of input video.

The display apparatus 100 may further include a tuner and a demodulator,according to an implementation. The tuner may tune a channel selected bythe user among radio frequency (RF) broadcasting signals receivedthrough an antenna or all pre-stored channels to receive an RFbroadcasting signal. The demodulator may receive and demodulate adigital intermediate frequency (DIF) signal converted by the tuner andperform channel demodulation, or the like. According to an embodiment,an input video received through the tuner may be processed through thedemodulator and be then provided to the processor 130 for videoprocessing according to an embodiment.

The above-described embodiments may be applied to all electronicapparatuses capable of performing video processing, such as a videoreceiving apparatus such as a set-top box, a video processing apparatus,as well as the display apparatus.

Embodiments may be implemented in a computer or an apparatus similar tothe computer using software, hardware, or a combination of software andhardware. In some cases, embodiments described in the disclosure may beimplemented by a processor itself. According to a softwareimplementation, embodiments such as procedures and functions describedherein may be implemented by separate software modules. Each of thesoftware modules may perform one or more functions and operationsdescribed in the disclosure.

Software (e.g., the program) containing one or more instructions forperforming processing operations of the display apparatus 100 accordingto embodiments may be stored in a machine-readable (e.g.,computer-readable) storage medium (e.g., internal memory) or externalmemory. The instructions stored in a non-transitory computer-readablemedium cause a specific device to perform the processing operations ofthe display apparatus 100 according to embodiments when they areexecuted by a processor of the specific device.

The non-transitory computer-readable medium is not a medium that storesdata for a while, such as a register, a cache, a memory, or the like,but means a medium that semi-permanently stores data and is readable bythe device. Specific examples of the non-transitory computer-readablemedium may include a compact disk (CD), a digital versatile disk (DVD),a hard disk, a Blu-ray disk, a USB, a memory card, a ROM, and the like.

While embodiments have been particularly shown and described withreference to the drawings, the embodiments are provided for the purposesof illustration and it will be understood by one of ordinary skill inthe art that various modifications and equivalent other embodiments maybe made from the disclosure. Accordingly, the true technical scope ofthe disclosure is defined by the technical spirit of the appendedclaims.

What is claimed is:
 1. A display apparatus comprising: a communication interface comprising a circuit and configured to receive a video; a display panel operable at a first refresh rate or a second refresh rate, the second refresh rate having a frequency higher than a frequency of the first refresh rate; and at least one processor configured to: control the display apparatus to operate a first mode or a second mode, control the display panel to output the video by maintaining an input frame rate of the video in the first mode of the display apparatus, and control the display panel to output the video by adjusting the input frame rate of the video to a second frame rate among a first frame rate and the second frame rate in the second mode of the display apparatus, the second frame rate corresponds to the second refresh rate.
 2. The display apparatus as claimed in claim 1, wherein the at least one processor configured to: based on the input frame rate of the video corresponding to the first frame rate, control the display panel to operate at the first refresh rate to output the video to the first frame rate, in the first mode of the display apparatus, and based on the input frame rate of the video corresponding to the second frame rate, control the display panel to operate at the second refresh rate to output the video to the second frame rate, in the first mode of the display apparatus.
 3. The display apparatus as claimed in claim 1, wherein the first frame rate corresponds to the first refresh rate, and wherein the first mode is for minimizing a delay that occurs between an input and an output of the video.
 4. The display apparatus as claimed in claim 1, wherein the at least one processor configured to: based on the input frame rate of the video corresponding to the first frame rate, change the input frame rate of the video from the first frame rate to the second frame rate and control the display panel to operate at the second refresh rate to output the video to the second frame rate, in the second mode of the display apparatus, and based on the input frame rate of the video corresponding to the second frame rate, maintain the input frame rate of the video and control the display panel to operate at the second refresh rate to output the video to the second frame rate, in the second mode of the display apparatus.
 5. The display apparatus as claimed in claim 1, wherein the at least one processor is further configured to adjust a dynamic capacitance compensation (DCC) value of the display panel based on whether the display panel operates at the first frame rate or the second frame rate, and wherein a first DCC value corresponding to the first frame rate of the display panel is greater than a second DCC value corresponding to the second frame rate of the display panel.
 6. The display apparatus as claimed in claim 5, wherein the at least one processor adjusts a liquid crystal charging timing of the display panel based on whether the display panel operates at the first frame rate or the second frame rate, and wherein a first liquid crystal charging timing corresponding to the first frame rate of the display panel is greater than a second liquid crystal charging timing corresponding to the second frame rate of the display panel.
 7. The display apparatus as claimed in claim 5, wherein the at least one processor is further configured to: based on a mode of the display apparatus being changed from the first mode to the second mode, increase the DCC value and a liquid crystal charging timing based on a setting value corresponding to the first frame rate, and adjust a luminance of the display panel so that a gamma value of the display panel is maintained to be equal to a reference gamma value.
 8. The display apparatus as claimed in claim 1, wherein the at least one processor is further configured to: control the display panel to display a user interface (UI) for changing a refresh rate of the display panel, and adjust a setting value of the display panel so that the display panel operates at the refresh rate corresponding to an user command for changing the refresh rate of the display panel input through the UI.
 9. The display apparatus as claimed in claim 1, wherein the at least one processor is further configured to identify the input frame rate of the video based on metadata of the video.
 10. A control method of a display apparatus comprising a display panel operable at a first refresh rate or a second refresh rate, the control method comprising: receiving a video; controlling the display apparatus to operate a first mode or a second mode; controlling the display panel to output the video by maintaining an input frame rate of the video in the first mode of the display apparatus; and controlling the display panel to output the video by adjusting the input frame rate of the video to a second frame rate among a first frame rate and the second frame rate in the second mode of the display apparatus, the second frame rate corresponds to the second refresh rate.
 11. The control method as claimed in claim 10, wherein the controlling the display panel in the first mode of the display apparatus further comprising: based on the input frame rate of the video corresponding to the first frame rate, controlling the display panel to operate at the first refresh rate to output the video to the first frame rate, in the first mode of the display apparatus, and based on the input frame rate of the video corresponding to the second frame rate, controlling the display panel to operate at the second refresh rate to output the video to the second frame rate, in the first mode of the display apparatus.
 12. The control method as claimed in claim 10, wherein the first frame rate corresponds to the first refresh rate, and wherein the first mode is for minimizing a delay that occurs between an input and an output of the video.
 13. The control method as claimed in claim 10, wherein the controlling the display panel in the second mode of the display apparatus further comprising: based on the input frame rate of the video corresponding to the first frame rate, changing the input frame rate of the video from the first frame rate to the second frame rate and controlling the display panel to operate at the second refresh rate to output the video to the second frame rate, in the second mode of the display apparatus, and based on the input frame rate of the video corresponding to the second frame rate, maintaining the input frame rate of the video and controlling the display panel to operate at the second refresh rate to output the video to the second frame rate, in the second mode of the display apparatus.
 14. The control method as claimed in claim 10, wherein the control method further comprises adjusting a dynamic capacitance compensation (DCC) value of the display panel, based on whether the display operates at the first frame rate or the second frame rate, and wherein a first DCC value corresponding to the first frame rate of the display panel are greater than a second DCC value corresponding to the second frame rate of the display panel.
 15. The control method as claimed in claim 14, further comprising: adjusting a liquid crystal charging timing of the display panel based on whether the display panel operates at the first frame rate or the second frame rate, and wherein a first liquid crystal charging timing corresponding to the first frame rate is greater than a second liquid crystal charging timing corresponding to the second frame rate of the display panel.
 16. The control method as claimed in claim 14, further comprising: based on a mode of the display apparatus being changed from the first mode to the second mode, increasing the DCC value and a liquid crystal charging timing based on a setting value corresponding to the first frame rate; and adjusting a luminance of the display panel so that a gamma value of the display panel is maintained to be equal to a reference gamma value.
 17. The control method as claimed in claim 10, further comprising: displaying a user interface (UI) for changing a refresh rate of the display panel, and adjusting a setting value of the display panel so that the display panel operates at a refresh rate corresponding to an user command for changing the refresh rate of the display panel input through the UI.
 18. The control method as claimed in claim 10, further comprising identifying the input frame rate of the video based on metadata of the received video. 